Fig. 5

EIF4A3 promotes the cyclization and cytoplasmic export of circCCAR1. A Five positions (a-e) in circCCAR1 pre-mRNA were selected to design qPCR primers, and three plasmids (A1-A3) containing EIF4A3 binding sites were constructed to pull down the EIF4A3 protein. B The interaction between EIF4A3 and circCCAR1 pre-mRNA was confirmed by RIP assay. ***p < 0.001 vs. IgG. C EIF4A3 protein was measured in the MS2-RNA pulldown complex. D EIF4A3 levels in HCC tissues and their paracancerous tissues were measured. ***p < 0.001. E The relationship between EIF4A3 and circCCAR1 levels in HCC samples was calculated. F The association of EIF4A3 expression and overall survival in HCC patients. G-H The expression of circCCAR1 in HCCLM3 and SK-Hep-1 cells with EIF4A3 depletion or overexpression. ***p < 0.001 vs. sh-NC or vector. I The binding of EIF4A3 and circCCAR1 was confirmed by RIP assay. ***p < 0.001 vs. IgG. J EIF4A3 protein level in pulldown assays using biotinylated antisense oligomer. K-M Nuclear–cytoplasmic fractionation and FISH-IF assays were used to assess the cytoplasmic export of circCCAR1 in HCC cells after EIF4A3 depletion. **p < 0.01, ***p < 0.001 vs. sh-NC